Although pesticide regulatory tools are mainly based on individual substances, aquatic ecosystems are usually exposed to multiple pesticides from their use on the variety of crops within the catchment of a river. This...Although pesticide regulatory tools are mainly based on individual substances, aquatic ecosystems are usually exposed to multiple pesticides from their use on the variety of crops within the catchment of a river. This study estimated the impact of measured pesticide mixtures in surface waters from 2002 and 2008 within three important Portuguese river basins（＇Mondego＇, ＇Sado＇ and ＇Tejo＇） on primary producers, arthropods and fish by toxic pressure calculation. Species sensitivity distributions（SSDs）, in combination with mixture toxicity models, were applied. Considering the differences in the responses of the taxonomic groups as well as in the pesticide exposures that these organisms experience, variable acute multi-substance potentially affected fractions（ms PAFs） were obtained. The median msP AF for primary producers and arthropods in surface waters of all river basins exceeded 5%, the cut-off value used in the prospective SSD approach for deriving individual environmental quality standards. A ranking procedure identified various photosystem II inhibiting herbicides, with oxadiazon having the relatively largest toxic effects on primary producers, while the organophosphorus insecticides, chlorfenvinphos and chlorpyrifos, and the organochloride endosulfan had the largest effects on arthropods and fish, respectively. These results ensure compliance with European legislation with regard to ecological risk assessment and management of pesticides in surface waters.展开更多
The digitization of administrative activities is a technique that not only optimizes resources, but also professionalizes the working methods of public and private services. This dematerialization process involves tec...The digitization of administrative activities is a technique that not only optimizes resources, but also professionalizes the working methods of public and private services. This dematerialization process involves technologies based on computer equipment, which, after use, becomes cumbersome waste. The aim targeted consisted of taking stock of the management of waste computer equipment imported into the Republic of Guinea, with a view of proposing a mode of environmentally sustainable management methods in a short time. To achieve this, the data was collected through investigation methods (observations, interviews, and questionnaires). This study reveals an excess of imports of electrical and electronic equipment in general, and computer equipment in particular, over the last ten years (2009-2019), With an import rate ranging from 4.03 to 54.45%. This study demonstrated the different ways in which computer and electronic equipment of all kinds are managed, with her failings. This study demonstrated the different ways in which computer and electronic equipment of all kinds are managed, as well as their failings. For this purpose, the different ways in which electronic waste is managed by different users were identified as storage, recycling, or rejection into nature or at waste storage points, often mixed with household waste. Companies specializing in the management of this type of waste and the presence of a certain number of regulatory texts almost do not exist. One company is only for the entire country but unknown to the majority of users.展开更多
Soil water management plays an important role in the response of kiwi plants （Actinidia deliciosa A. Chev.）. In GuimarSes district soil moisture content is monitored in kiwifi＇uit orchard as a routine parameter. Dr...Soil water management plays an important role in the response of kiwi plants （Actinidia deliciosa A. Chev.）. In GuimarSes district soil moisture content is monitored in kiwifi＇uit orchard as a routine parameter. Drip irrigation system is the method used. This crop tends to have high water requirements and extends over a wide area in Portugal, requiring innovative solutions to achieve better benefits. A method that correlates soil and crop conditions with the parameters of remote sensing was established in this study. To assess the level of accuracy of soil moisture measurements from satellites, it is important to compare satellite image with ground real data （namely the frequency domain reflectometry （FDR）, Diviner 2000）. The combination of multispectral satellite images produces an image representative of vegetation vigour, density and health. In this study, Landsat satellite images （2011 and 2013） are used and vegetation indexes are calculated for different periods of time, using the software Idrisi Taiga. The information of vegetation indexes is crossed with data of soil moisture, in situ, to establish a correlation between both of them. Thus, it allows to improve the soil water content monitoring, in particular for the soil water balance optimization and its effect on kiwi biornass production.展开更多
A steel dual-core self-centering brace （DC-SCB） is an innovative structural member that provides both energy dissipation and self-centering properties to structures, reducing maximum and residual drifts of structure...A steel dual-core self-centering brace （DC-SCB） is an innovative structural member that provides both energy dissipation and self-centering properties to structures, reducing maximum and residual drifts of structures in earthquakes. The axial deformation capacity of the DC-SCB is doubled by a parallel arrangement of two inner cores, one outer box and two sets of tensioning elements. This paper presents cyclic test results of a DC-SCB component and a full- scale one-story, one-bay steel frame with a DC-SCB. The DC-SCB that was near 8 m-long was tested to evaluate its cyclic behavior and durability. The DC-SCB performed well under a total of three increasing cyclic loading tests and 60 low- cycle fatigue loading tests without failure. The maximum axial load of the DC-SCB was near 1700 kN at an interstory drift of 2.5%. Moreover, a three-story dual-core self-centering braced frame （DC-SCBF） with a single-diagonal DC-SCB was designed and its first-story, one-bay DC-SCBF subassembly specimen was tested in multiple earthquake-type loadings. The one-story, one-bay subassembly frame specimen performed well up to an interstory drift of 2% with yielding at the column base and local buckling in the steel beam; no damage of the DC-SCB was found after all tests. The maximum residual drift of the DC-SCBF caused by beam local buckling was 0.5% in 2.0% drift cycles.展开更多
The degradation of benzene, a carcinogenic air pollutant, was studied in a gas-phase photochemical reactor with an amalgam lamp emitting ultraviolet light at 185 and 254 nm. Efficient benzene degradation （〉70%） was...The degradation of benzene, a carcinogenic air pollutant, was studied in a gas-phase photochemical reactor with an amalgam lamp emitting ultraviolet light at 185 and 254 nm. Efficient benzene degradation （〉70%） was possible for benzene mass flow rates of up to 1.5 mg.min1. Adding ozone allowed benzene mass flow rates of up to 5 m g.min-1 tobe treated with the same efficiency. In terms of energy consumption, ozone doubles the efficiency of the process. A comprenenslve mecnanisnc simulation model was developed incorporating a chemical kinetics model （62 reactions involving 47 chemical species）, a material balance model incorporating diffusion and flow, a flow velocity model,and a light field model. The model successfully predicted the efficiency of the reactor, generally within 20%, which indicates that the model is sound, and can be used for feasibility studies. The prediction of the reactor efficiency in the presence of ozone was less successful, with systematically overestimated efficiency. Condensation of reaction products in the reactor is thought to be the mare cause of model inaccuracy. Both experimental .data and model predictions show that there is a synergistic effect between ozonation and ultraviolet degradation.展开更多
文摘Although pesticide regulatory tools are mainly based on individual substances, aquatic ecosystems are usually exposed to multiple pesticides from their use on the variety of crops within the catchment of a river. This study estimated the impact of measured pesticide mixtures in surface waters from 2002 and 2008 within three important Portuguese river basins（＇Mondego＇, ＇Sado＇ and ＇Tejo＇） on primary producers, arthropods and fish by toxic pressure calculation. Species sensitivity distributions（SSDs）, in combination with mixture toxicity models, were applied. Considering the differences in the responses of the taxonomic groups as well as in the pesticide exposures that these organisms experience, variable acute multi-substance potentially affected fractions（ms PAFs） were obtained. The median msP AF for primary producers and arthropods in surface waters of all river basins exceeded 5%, the cut-off value used in the prospective SSD approach for deriving individual environmental quality standards. A ranking procedure identified various photosystem II inhibiting herbicides, with oxadiazon having the relatively largest toxic effects on primary producers, while the organophosphorus insecticides, chlorfenvinphos and chlorpyrifos, and the organochloride endosulfan had the largest effects on arthropods and fish, respectively. These results ensure compliance with European legislation with regard to ecological risk assessment and management of pesticides in surface waters.
文摘The digitization of administrative activities is a technique that not only optimizes resources, but also professionalizes the working methods of public and private services. This dematerialization process involves technologies based on computer equipment, which, after use, becomes cumbersome waste. The aim targeted consisted of taking stock of the management of waste computer equipment imported into the Republic of Guinea, with a view of proposing a mode of environmentally sustainable management methods in a short time. To achieve this, the data was collected through investigation methods (observations, interviews, and questionnaires). This study reveals an excess of imports of electrical and electronic equipment in general, and computer equipment in particular, over the last ten years (2009-2019), With an import rate ranging from 4.03 to 54.45%. This study demonstrated the different ways in which computer and electronic equipment of all kinds are managed, with her failings. This study demonstrated the different ways in which computer and electronic equipment of all kinds are managed, as well as their failings. For this purpose, the different ways in which electronic waste is managed by different users were identified as storage, recycling, or rejection into nature or at waste storage points, often mixed with household waste. Companies specializing in the management of this type of waste and the presence of a certain number of regulatory texts almost do not exist. One company is only for the entire country but unknown to the majority of users.
文摘Soil water management plays an important role in the response of kiwi plants （Actinidia deliciosa A. Chev.）. In GuimarSes district soil moisture content is monitored in kiwifi＇uit orchard as a routine parameter. Drip irrigation system is the method used. This crop tends to have high water requirements and extends over a wide area in Portugal, requiring innovative solutions to achieve better benefits. A method that correlates soil and crop conditions with the parameters of remote sensing was established in this study. To assess the level of accuracy of soil moisture measurements from satellites, it is important to compare satellite image with ground real data （namely the frequency domain reflectometry （FDR）, Diviner 2000）. The combination of multispectral satellite images produces an image representative of vegetation vigour, density and health. In this study, Landsat satellite images （2011 and 2013） are used and vegetation indexes are calculated for different periods of time, using the software Idrisi Taiga. The information of vegetation indexes is crossed with data of soil moisture, in situ, to establish a correlation between both of them. Thus, it allows to improve the soil water content monitoring, in particular for the soil water balance optimization and its effect on kiwi biornass production.
文摘A steel dual-core self-centering brace （DC-SCB） is an innovative structural member that provides both energy dissipation and self-centering properties to structures, reducing maximum and residual drifts of structures in earthquakes. The axial deformation capacity of the DC-SCB is doubled by a parallel arrangement of two inner cores, one outer box and two sets of tensioning elements. This paper presents cyclic test results of a DC-SCB component and a full- scale one-story, one-bay steel frame with a DC-SCB. The DC-SCB that was near 8 m-long was tested to evaluate its cyclic behavior and durability. The DC-SCB performed well under a total of three increasing cyclic loading tests and 60 low- cycle fatigue loading tests without failure. The maximum axial load of the DC-SCB was near 1700 kN at an interstory drift of 2.5%. Moreover, a three-story dual-core self-centering braced frame （DC-SCBF） with a single-diagonal DC-SCB was designed and its first-story, one-bay DC-SCBF subassembly specimen was tested in multiple earthquake-type loadings. The one-story, one-bay subassembly frame specimen performed well up to an interstory drift of 2% with yielding at the column base and local buckling in the steel beam; no damage of the DC-SCB was found after all tests. The maximum residual drift of the DC-SCBF caused by beam local buckling was 0.5% in 2.0% drift cycles.
文摘The degradation of benzene, a carcinogenic air pollutant, was studied in a gas-phase photochemical reactor with an amalgam lamp emitting ultraviolet light at 185 and 254 nm. Efficient benzene degradation （〉70%） was possible for benzene mass flow rates of up to 1.5 mg.min1. Adding ozone allowed benzene mass flow rates of up to 5 m g.min-1 tobe treated with the same efficiency. In terms of energy consumption, ozone doubles the efficiency of the process. A comprenenslve mecnanisnc simulation model was developed incorporating a chemical kinetics model （62 reactions involving 47 chemical species）, a material balance model incorporating diffusion and flow, a flow velocity model,and a light field model. The model successfully predicted the efficiency of the reactor, generally within 20%, which indicates that the model is sound, and can be used for feasibility studies. The prediction of the reactor efficiency in the presence of ozone was less successful, with systematically overestimated efficiency. Condensation of reaction products in the reactor is thought to be the mare cause of model inaccuracy. Both experimental .data and model predictions show that there is a synergistic effect between ozonation and ultraviolet degradation.
